Gas generator



Jan., 21, 1941. R. R. HAMMER ETAL 2,229,452

' GAS GENERATOR Filed Deo. 7, 1939 III/la lll/Ill nvenToTs. Ralph R. Hummer Frank AMucCqllum by/zMMkM Ays.

Patented Jan. 21, 1941 UNITED STATES PATENT GFFICE 2,229,452 GAS GENERATOR Application December 7, 1939, Serial No. 303,018

2 Claims.

`This invention relates to that type of gas generator which is provided with means for passing air through a body of liquid hydrocarbon, thereby to generate a combustible gas, the air as it passes 5 through the liquid hydrocarbon absorbing or becoming impregnated with themost volatile hydrocarbon ingredients. Where the liquid hydrocarbon used is gasoline, the volatile ingredients evaporated from the liquid are hexane, methane, etc.

In the operation of gas generators of this type, the continued passage of air through a body of liquid hydrocarbon will gradually exhaust it of its more volatile hydrocarbon ingredients. Hence if the passage of air through such body of liquid hydrocarbon is continued without the addition of fresh liquid hydrocarbon, the air will pick up a gradually decreasing quantity of hydrocarbon with the result that the gas which is thus produced will finally be lean gas and one unfit for ordinary use. l

When this condition exists, then it becomes necessary to replace the exhausted liquid hydrocarbon with a fresh supply. Such exhausted liquid hydrocarbon is frequently referred to as strip oil.

It is one of the objects of our present invention to provide a gas generating apparatus with means by which fresh liquid hydrocarbon will be delivered to the body of liquid hydrocarbon from which the gas is being generated as occasion demands, and at the same time, a compensating amount of strip oil will be removed from the body of liquid hydrocarbon, thereby maintaining such 35 liquid hydrocarbon continuously in a condition to generate gas of a uniform good quality.

In carrying out our invention, we provide a suitable generator tank to contain the liquid hydrocarbon and also provide an inlet valve for sup- 40 plying fresh liquid hydrocarbon thereto, and further provide a discharge valve near the bottom of the tank through which the strip oil may be Withdrawn from the tank.

We also provide means controlled by the liquid 45 level in the tank to open the inlet valve when the liquid level falls below a predetermined point, and simultaneously to open the discharge valve so that there will be a discharge of the strip oil from the tank at the same time that the fresh liquid hydrocarbon is supplied thereto.

The relative size of the inlet Valve and discharge valve is` such that when both valves are opened, the amount delivered through the discharge valve is considerably less than that delivered through the inlet valve; this being desirable because the amount of strip oil which results from the exhaustion of any given amount of liquid hydrocarbon is, of course, very much less than the said given amount, usually about 30% of said amount. The inlet and discharge valves, 5 therefore, will preferably be arranged so that when both valves are opened, the inlet valve will deliver fresh liquid hydrocarbon to the tank about three times as fast as the strip oil is withdrawn from the bottom of the tank.

The apparatus controlling the valves is so constructed that when the liquid level in the tank falls below a predetermined amount, both valves will be automatically opened, and as the inlet Y valve is delivering liquid to the tank faster than l5 the discharge valve is withdrawing it therefrom, the liquid level will gradually rise in the tank. When the liquid level has again reached its normal point, then the valves are automatically closed. This feature of our invention, therefore, 20 provides foi` automatically withdrawing the strip oil from the tank as the fresh liquid hydrocarbon is delivered thereto.

The operation of the inlet and discharge valves is controlled by a float in the tank, and another 25 feature of our invention relates to means whereby the operation of the float will not be disturbed by any bubbling or boiling condition of the liquid hydrocarbon due to the passage of the air therethrough. To provide for this, we propose to di- 30 vide the tank by a vertical partition into two compartments which communicate with each other so that the liquid level in both compartments will be the same. Ihe air is passed through the liquid hydrocarbon in one compartment while the oat is located in the other compartment. Any ebullition of the liquid hydrocarbon due to the air passing therethrough will not, therefore, affect in any way the action of the float.

These, and other features of our invention, will be more fully hereinafter set forth and then pointed out in the appended claims.

In the drawing Fig. 1 is a somewhat diagrammatic view illustrating a device embodying our invention, the tank containing the liquid hydrocarbon being shown in section.

Fig. 2 is a partial sectional plan View illustrating the float actuated means for controlling the inlet and discharge valves.

In the drawing, l indicates a tank adapted to contain liquid hydrocarbon 2. 3 is an air supply pipe leading into said tank and having at its end an open bottomed chamber 4 into which air is delivered, said chamber 4 being sub- 55 merged in the liquid hydrocarbon 2 in the tank. The top wall 5 of the chamber is provided with perforations 6 for the passage of air. The air to be carbureted is caused to be passed through liquid hydrocarbon 2 by means of a suction apparatus 7, the inlet to which is connected by a pipe 8 to the top of the tank I and the outlet of which is connected by a pipe 9 to any suitable storage tank I0, said pipe having a check valve 4G therein. The suction apparatus 'I may be of any suitable or usual type, and it is shown as being actuated by a suitable electric motor Il which is connected to the suction apparatus by suitable driving belt I2. When the suction apparatus 'I is in operation, a reduced pressure will be developed in the upper portion I3 of the tank I, and this reduced pressure will result in drawing the air into the tank through the air inlet pipe 3. As this air passes through the liquid hydrocarbon, it absorbs therefrom some of the more voluble hydrocarbon ingredients, thereby producing a combustible gas which is well adapted for use in gas stoves or gas heaters, or even in internal combustion engines. This gas is delivered to the storage tank I from which it is distributed to the apparatus in which it is to be used. |There is herein shown a delivery pipe Ill connected to the tank IB and leading to the place of consumption of the gas, said pipe Ic having any suitable pressure regulator I therein which serves to maintain a constant desired pressure on its delivery side.

The continued passage of air through the liquid hydrocarbon 2 gradually exhausts the more volatile hydrocarbon ingredients, and during this operation, the portion of the liquid hydrocarbon from which the most volatile ingredients have been carried olf, and which is frequently referred to as strip oil, gradually accumulates in the bottom of the tank due to its greater specific gravity.

In order to secure the generation of gas of a uniform quality continuously, we propose to provide means for admitting fresh liquid hydrocarbon to the tank I as occasion demands in order to maintain approximately a uniform liquid level in said tank, and also to provide means for withdrawing a compensating amount of strip oil from the bottom of the tank simultaneously with the admission of the fresh liquid hydrocarbon to the tank. In this way, the portion o f the contents of the tank through which the air passes will always be rich in the most volatile hydrocarbon elements, and a sufficient amount of the strip oil will be withdrawn from the tank to maintain the liquid level therein at the desired point.

The liquid hydrocarbon is supplied to the tank I through a suitable supply pipe I5 provided with an inlet valve I6 and said supply pipe is shown asbeing connected to a suitable supply reservoir Il. Connected. to the tank I at its bottom is a discharge pipe I3 which leads to a. receptacle le into which the strip oil is drained, and this discharge pipe is controlled by suitable valve mechanism constructed so that the rate of flow therethrough will be considerably less than that through the inlet valve when both valves are open. The discharge valve mechanism herein illustrated comprises a valve member ZIJ and a second valve 2| which can be manually adjusted to permit the desired reduced flow as compared with the normal iow through the inlet valve IB when the latter is opened.

We have provided herein means controlled by the liquid level in the tank I and which is rendered operative when the liquid level falls below a predetermined point to open both the inlet valve I E and the discharge valve, thereby to allow fresh liquid hydrocarbon to flow into the tank, and at the same time to provide for draining the tank 2 of part of its strip oil. Inasmuch as the inlet valve I6 will admit liquid hydrocarbon to the tank faster than the discharge valve mechanism will allow the discharge of strip oil from the tank, the liquid level in the tank will gradually rise when both valves are opened. The controlling means above referred to is so constructed that when the liquid level in the tank reaches its normal point, then both the inlet valve I6 and.

the discharge valve mechanism are closed, said valves remaining closed until the liquid level again falls below the critical point.

While various devices designed to accomplish this end may be employed, we have shown magnetic valves and have also shown a float in the tank I arranged to open and close said valves as the liquid level in said tank falls and rises.

The float for controlling the valves is indicated at 22 and it is connected by a link connection 23 with a lever 24 pivoted at 25 to a xed support 2G. One end of this lever is connected by a link connection 2l to one end of an arm 28 which is rigid with a shaft 29 that extends through the wall of the tank I and is journaled in suitable bearings 3B carried by the wall. At the outer end of the shaft is a mercoid tube 3|, this being one well known form of mercury switch for controlling an electric circuit. This mercoid tube is connected in an electric circuit 32 which has one branch 33 leading to the inlet valve I6 and another branch 34 leading lto the discharge valve 2c. The circuit 32 issupplied with current from any suitable source of supply, as, for instance,.

the line wires 35 which supply current to the motor II.

If it be assumed that the valves I6 and 20 are closed in Fig. 1, the continued passing of the air through the liquid hydrocarbon 2 to create the combustible gas will cause a gradual lowering of the liquid level in the tank I, and as the level lowers, the float 22 will descend, thereby turning the shaft 29 and mercoid tube 3| in a counterclockwise direction. When the liquid level in the tank I has reached a predetermined point, the mercoid tube 3| will have turned into a position so that the movement of the mercury in said tube to the lower end thereof will close the circuit 32,

thereby actuating the valves I5 and 20 and causing said valves to open.

Fresh liquid hydrocarbon will then iiow into the tank I from the supply reservoir II and simultaneously strip oil will be discharged from the tank I into the reservoir I9, the amount of strip( oil discharged in any given time being considerably less than the amount of liquid hydrocarbon which is delivered to the tank in the same time because of the adjustment of the valves 2B and 2l. Since the amount of fresh liquid hydrocarbon delivered to the tank I is greater than the amount of strip oil which is withdrawn, the liquid level in the tank will gradually rise again, and when it reaches the critical point, the mercoid tube will have been turned into a position to open the circuit 32, thereby permitting the valves I6 and 2E! to close.

The valves I6 and 26 will thus be opened automatically whenever there is need for an additional supply of fresh liquid hydrocarbon to the tank, and said valves will be closed automatically when the normal liquid level in said tank has been regained.

The passage of the air through the liquid hydrocarbon will produce a more or less violent ebullition thereof, and in order to prevent such agitation of the liquid hydrocarbon from affecting the operation of the oat 22, we propose to provide the tank with a vertical partition 36, which is herein shown as cylindrical in form and which divides the tank into two compartments, 31 and 38. This partition is provided at its lower end with a plurality of apertures 39 which provide a communication between the compartments 31 and 38, so that the liquid level in the two compartments will be the same. The float 22 is in the compartment 38 and the chamber 4 through which the air is delivered to the liquid hydrocarbon is located in the compartment 31. Hence the ebullition induced in the liquid hydrocarbon by the passage of the air therethrough will occur entirely in the compartment 31, and the liquid in the compartment 38 will be quiescent so that the float 22 will only be affected by the change in level of the liquid and will not be affected by any Violent boiling or ebullition of the liquid hydrocarbon due to the passage of the air therethrough.

We propose to employ a blower element 1 of the centrifugal type capable of delivering a maximum pressure somewhat above the pressure delivered by the pressure regulator I5, and to op-` erate said blower continuously. With this arrangement, so long as the pressure in the tank Il] is below the maximum pressure, then said blower will be sucking air through the liquid hydrocarbon in the tank I and delivering the combustible gas to the tank I0. If at any time the pressure in the tank I0 builds up to its maximum point, then the blower 1 will simply idle and will, therefore, require a minimum amount of electricity for its operation due to the fact that it is doing no work. As soon, however, as the consumption of the gas from the tank I 0 results in a lowering of the pressure in the tank below the maximum, then the continually rotating blower 1 will automatically begin to operate to draw more air through the liquid hydrocarbon 2 and thus deliver more gas to the tank I. The blower which it is necessary to use is one which has a maximum rate of delivery slightly greater than the maximum rate at which gas will be used from the tank I0.

40 indicates an electric heater located in the tank I for heating the liquid hydrocarbon therein, said heater being supplied with current through a suitable circuit 4I.

The operation of the heater 4D may be controlled by any suitable thermostat (not shown) which will be mounted so as to be responsive to changes in the temperature of the liquid hydrocarbon.

We have shown means for varying the effective weight of the float 22 so as to provide for submerging it to the required point for most effective operation. As herein illustrated, the support for the mercoid tube 3| is provided with an adjustable counterweight 43 and the lever 24 is provided with an adjustable counterweight 42. By adjusting these weights the degree of submergence of the float 22 can be varied, thereby varying the sensitiveness of the apparatus.

41 indicates a drain pipe leading from the storage tank I0 to the receptacle I9 for the strip oil, said pipe having a trap 48 therein. The purpose of this pipe is to provide for draining into the tank I9 any liquid which will be developed in the tank I0 by condensation.

49 indicates a vent pipe leading from the tank I9 to the atmosphere.

While any suitable liquid hydrocarbon may be used in the apparatus for generating a combustible gas, yet we prefer to use gasoline since this is a liquid hydrocarbon which can be purchased anywhere and is of a character that will generate a combustible gas eminently suited for gas stoves, heaters or even gas engines.

While we have illustrated herein a selected embodiment of the invention, we do not wish to be vlimited to the constructional features shown.

We claim:

1. A gas generator comprising a tank adapted to contain liquid hydrocarbon, means to pass air through the liquid hydrocarbon in said tank, thereby to generate a combustible gas, an inlet valve to supply fresh liquid hydrocarbon to the tank, a discharge valve through which strip oil may be withdrawn from the bottom of the tank but at a slower rate than that a which the fresh liquid hydrocarbon is delivered to the tank, a float in said tank, and electrically actuated means controlled by the falling and rising movement of said iioat as the liquid level in the tank falls and rises to open both valves simultaneously when the liquid level in the tank falls below a predetermined point, whereby fresh liquid hydrocarbon will be supplied to the tank at the same time that strip oil is being discharged from the bottom of the tank at a rate slower than that a which the fresh hydrocarbon is delivered to the tank, thus producing a rise in the liquid level in the tank while both valves are open, said means being operative to close both of said valves simultaneously when the liquid level again rises to said predetermined point.

2. A gas generator comprising a tank adapted to contain liquid hydrocarbon, means to pass air through said liquid hydrocarbon, thereby to generate a combustible gas, an inlet valve controlling the supply of liquid hydrocarbon to said tank, a discharge pipe connected to the tank at its lower end and through which strip oil may be discharged, a discharge valve in said pipe, which valve, when open, permits a flow at a slower rate than the open inlet valve, and means rendered operative to open both valves simultaneously when the liquid level in the tank falls below a predetermined point, whereby fresh liquid hydrocarbon will be supplied to the tank at the same time that strip oil is being discharged from the bottom of the tank, but at a rate slower than that at which the fresh hydrocarbon is delivered to the tank, thus producing a rise in the liquid level in the tank while both valves are open, said means being operative to close both valves simultaneously when the liquid level again rises to a' predetermined point.

RALPH R. HAMMER. FRANK A. MACCALLUM. 

